An issue was discovered on Moxa AWK-3121 1.14 devices. It provides functionality so that an administrator can run scripts on the device to troubleshoot any issues. However, the same functionality allows an attacker to execute commands on the device. The POST parameter "iw_filename" is susceptible to command injection via shell metacharacters.
https://seclists.org/bugtraq/2019/Jun/8
https://github.com/samuelhuntley/Moxa_AWK_1121/blob/master/Moxa_AWK_1121